package com.sky.service.impl;

import com.github.pagehelper.Page;
import com.github.pagehelper.PageHelper;
import com.sky.constant.MessageConstant;
import com.sky.constant.StatusConstant;
import com.sky.dto.DishDTO;
import com.sky.dto.DishPageQueryDTO;
import com.sky.entity.Dish;
import com.sky.entity.DishFlavor;
import com.sky.exception.DeletionNotAllowedException;
import com.sky.mapper.DishFlavorMapper;
import com.sky.mapper.DishMapper;
import com.sky.mapper.SetmealDishMapper;
import com.sky.result.PageResult;
import com.sky.service.DishService;
import com.sky.vo.DishVO;
import org.springframework.beans.BeanUtils;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

import java.util.ArrayList;
import java.util.Collections;
import java.util.List;

@Service
public class DishServiceImpl implements DishService {

    /// 构造函数注入
    private final DishMapper dishMapper;
    private final DishFlavorMapper dishFlavorMapper;
    private final SetmealDishMapper setmealDishMapper;

    public DishServiceImpl(DishMapper dishMapper, DishFlavorMapper dishFlavorMapper, SetmealDishMapper setmealDishMapper) {
        this.dishMapper = dishMapper;
        this.dishFlavorMapper = dishFlavorMapper;
        this.setmealDishMapper = setmealDishMapper;
    }

    /**
     * 新增菜品和对应的口味
     *
     * @param dishDTO
     */
    @Transactional//事务管理，要么全成功，要么全失败，要操作两张表，保证数据的一致性
    @Override
    public void saveWithFlavor(DishDTO dishDTO) {

        Dish dish = new Dish();

        BeanUtils.copyProperties(dishDTO, dish);

        //向菜品表插入一条数据
        dishMapper.insert(dish);

        //获取insert插入的主键值
        Long dishId = dish.getId();

        //向口味表插入多条数据
        List<DishFlavor> flavors = dishDTO.getFlavors();

        if (flavors != null && !flavors.isEmpty()) {
            //遍历赋值
            flavors.forEach(dishFlavor -> {
                dishFlavor.setDishId(dishId);
            });

            //插入N条数据--批量插入
            dishFlavorMapper.insertBatch(flavors);
        }
    }

    /**
     * 菜品分页查询
     *
     * @param dishPageQueryDTO
     * @return
     */
    @Override
    public PageResult pageQuery(DishPageQueryDTO dishPageQueryDTO) {
        PageHelper.startPage(dishPageQueryDTO.getPage(), dishPageQueryDTO.getPageSize());
        Page<DishVO> page = dishMapper.pageQuery(dishPageQueryDTO);
        return new PageResult(page.getTotal(), page.getResult());

    }

    /**
     * 菜品的批量删除功能
     *
     * @param ids
     */
    @Transactional//事务注解保持数据的一致性
    @Override
    public void deleteBatch(List<Long> ids) {
        //判断当前菜品是否能删除--是否存在起售中的菜品
        for (Long id : ids) {
            Dish dish = dishMapper.getById(id);
            if (dish.getStatus() == StatusConstant.ENABLE) {
                //当前菜品处于起售中,不能删除
                throw new DeletionNotAllowedException(MessageConstant.DISH_ON_SALE);
            }
        }

        //判断当前菜品是否能删除--是否关联套餐
        List<Long> setmealIds = setmealDishMapper.getSetmealIdsByDishIds(ids);
        if (setmealIds != null && !setmealIds.isEmpty()) {
            //当前菜品被套餐关联了，不能删除
            throw new DeletionNotAllowedException(MessageConstant.DISH_BE_RELATED_BY_SETMEAL);
        }

        //删除菜品表的菜品数据
        dishMapper.deleteById(ids);

        //删除该菜品关联的口味数据
        dishFlavorMapper.deleteByDishId(ids);
    }

    /**
     * 根据id查询菜品和对应的口味数据
     *
     * @param id
     * @return
     */
    @Override
    public DishVO getByIdWithFlavor(Long id) {
        //根据id获取菜品数据
        Dish dish = dishMapper.getById(id);

        //根据菜品id来获取对应的口味
        List<DishFlavor> dishFlavorList = dishFlavorMapper.getByDishId(id);

        //将获取到的数据封装到VO
        DishVO dishVO = new DishVO();
        BeanUtils.copyProperties(dish, dishVO);
        dishVO.setFlavors(dishFlavorList);

        return dishVO;
    }

    /**
     * 修改菜品信息
     *
     * @param dishDTO
     */
    @Override
    public void updateWithFlavor(DishDTO dishDTO) {
        //拷贝对象
        Dish dish = new Dish();
        BeanUtils.copyProperties(dishDTO, dish);

        //修改菜品表的基本信息
        dishMapper.update(dish);

        //口味表:先删除原有的数据
        dishFlavorMapper.deleteByDishId(Collections.singletonList(dishDTO.getId()));

        //重新插入口味数据
        List<DishFlavor> flavors = dishDTO.getFlavors();

        if (flavors != null && !flavors.isEmpty()) {
            //遍历赋值
            flavors.forEach(dishFlavor -> {
                dishFlavor.setDishId(dishDTO.getId());
            });

            //插入n条数据
            dishFlavorMapper.insertBatch(flavors);
        }
    }

    /**
     * 修改菜品启用禁用状态
     *
     * @param status
     * @param id
     */
    @Override
    public void updateStatus(Integer status, Long id) {
        //设置对象
        Dish dish = Dish.builder()
                .id(id)
                .status(status)
                .build();

        //修改数据
        dishMapper.update(dish);
    }

    /**
     * 根据分类id查询菜品
     *
     * @param categoryId
     * @return
     */
    @Override
    public List<Dish> getById(Long categoryId) {
        return dishMapper.getDishsById(categoryId);
    }

    /**
     * 条件查询菜品和口味
     * @param dish
     * @return
     */
    public List<DishVO> listWithFlavor(Dish dish) {
        List<Dish> dishList = dishMapper.getDishsById(dish.getCategoryId());

        List<DishVO> dishVOList = new ArrayList<>();

        for (Dish d : dishList) {
            DishVO dishVO = new DishVO();
            BeanUtils.copyProperties(d,dishVO);

            //根据菜品id查询对应的口味
            List<DishFlavor> flavors = dishFlavorMapper.getByDishId(d.getId());

            dishVO.setFlavors(flavors);
            dishVOList.add(dishVO);
        }

        return dishVOList;
    }
}
